The present invention relates to a semiconductor device, which can be preferably used as a semiconductor device housing, for example, a high voltage tolerant transistor.
In a semiconductor device having a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), a so-called back gate region, from which a potential of a semiconductor substrate or a well region is extracted, may be formed. Semiconductor devices in each of which the back gate region is formed are disclosed in, for example, Japanese Unexamined Patent Publication No. 2002-43571 (Patent Document 1) and Japanese Unexamined Patent Publication No. 2011-204924 (Patent Document 2).    [Patent Document 1] Japanese Unexamined Patent Publication No. 2002-43571    [Patent Document 2] Japanese Unexamined Patent Publication No. 2011-204924